Washington -LRB- CNN -RRB- -- In rural southern Virginia , 14-term Democratic Rep. Rick Boucher says he 's never had an election enemy quite like the ones he 's facing this year .

Its not his opponent , but instead it 's what he calls a `` shadowy '' group that is funding television ads against him .

`` Rick Boucher is trying to deceive you ... Boucher has failed to protect our jobs . Now it 's time Rick Boucher loses his , '' the ad 's narrator says .

The 30-second commercial was paid for by Americans for Job Security , a conservative-leaning group which , according to the nonpartisan watchdog group OpenSecrets.org , has spent nearly $ 8 million against Democratic candidates nationwide .

On its website , Americans for Jobs Security states that its members are `` businesses , business leaders and entrepreneurs from around the country , '' but blatantly states it will not disclose the names of its individual members or donors .

Boucher , who says he 's spent $ 300,000 of his campaign funds to counter the ad , rails against the secretive nature of the organization .

`` We have no idea who these individuals are , '' Boucher said . `` It could be someone who has a corporate identity in the United States . It could be a very wealthy individual who has some grudge against me and is putting this advertisement on the air as a consequence . ''

Americans for Job Security identifies itself on its website as a 501 -LRB- c -RRB- -LRB- 6 -RRB- business league . That 's a tax status for a nonprofit operation that can be involved in politics but not as its primary purpose . This particular tax status also means it does not have to disclose its donors .

Read IRS regulations on 501 -LRB- c -RRB- -LRB- 6 -RRB- business leagues

Groups such as Americans for Job Security are outside the Democratic and Republican parties and are likely benefiting from a Supreme Court decision earlier this year . That ruling , made on free speech grounds , allows corporations and unions to spend unlimited money to help defeat or promote candidates .

That means even watchdog groups that track money flowing through elections ca n't find out who funds the groups .

`` When you 're just trying to figure out who is truly behind that television message that you 're seeing on TV , you do n't know who 's behind it , and that makes it more difficult as a voter to actually have the requisite information to go into the voting booth and make an informed choice , '' said Dave Levinthal of OpenSecrets.org .

Republican sources have told CNN that Americans for Job Security has only one full-time employee , Steve DeMaura . His office is in Alexandria , Virginia , across the Potomac River from Washington . CNN left multiple phone messages for DeMaura , but he did not return the calls .

Conservative-leaning outside groups have already spent $ 121.6 million this election season compared with $ 79.1 million spent by liberal-leaning outside groups , according to OpenSecrets.org .

Another conservative group , Americans for Prosperity , expects to raise and spend about $ 35 million this election .

`` We simply educate the public , '' said Tim Phillips , the group 's president .

Part of that money is funding a television ad running in Colorado targeting first-term Democratic Rep. Betsy Markey , which says , `` To small businesses , Betsy Markey is the same as Nancy Pelosi . ''

Who are Americans for Prosperity 's donors ? The Texas billionaire Koch brothers are the group 's founders and give significant dollars . But besides them , it 's unclear .

Phillips also makes no apologies for not revealing donors .

`` Most of it is private individuals , but we 're glad to have their support and we do tell them , ` Look we 're going to protect your privacy as the law allows us to do . ' ''

President Obama has made it a regular practice lately to call out Americans for Prosperity by name in his effort to attack outside groups for spending tens of millions against Democrats without disclosing donors .

`` They are now allowed to spend as much as they want , unlimited amounts of money , and they do n't have to reveal who is paying for these ads , '' Obama said at a recent Democratic fundraiser . `` Millions of dollars being spent by groups with harmless-sounding names , Americans for Prosperity , the Committee for Truth in Politics , or Moms for Motherhood . ''

Phillips said the president 's attacks have actually helped Americans for Prosperity raise more money .

`` If the president wants to use us as a punching bag , let him , '' he said . `` It does help funding , and it helps generate new grassroots support . ''

Despite tough talk from Obama targeting Republican-backed outside groups , it 's a mutual election-year undertaking .

Democrats have their own groups supporting them , such as Defenders of Wildlife Action Fund and Citizens for Strength and Security Action Fund , which are not disclosing their donors .

In New Mexico , where former Rep. Steve Pearce is running for his old seat , Defenders of Wildlife Action Fund is running an ad against him .

As eerie music plays in the background the narrator says , `` Congressman Steve Pearce , named one of the most corrupt members of Congress . ''

In Washington state , Citizens for Strength and Security Action Fund is running an ad promoting Democratic Sen. Patty Murray .

And Democrats have smaller outside groups aimed at getting Democratic voters to the polls .

Our Community Votes was originally started by veteran union strategist Steve Rosenthal . This year , according to an official familiar with the organization , it is running programs in Missouri , Maryland and Pennsylvania to encourage Democratic voters to go the polls . They 're targeting African-American voters and `` drop-off voters , '' those who went to the polls for Obama in 2008 but may not be likely to return for this year 's midterm election .

Our Community Votes is yet another Democratic group that does not disclose its donors .

Democrats are also using a new weapon in the big money game of politics : the super PAC .

Super PACs work independently of candidates . Unlike regular political action committees , they can raise and spend unlimited money to try to defeat or promote candidates . But super PACs must disclose their donors .

Patriot Majority is one of the biggest of these new groups , and it is concentrating its efforts in Nevada , spending at least $ 5 million so far on ads against Senate Majority Leader Harry Reid 's opponent , Republican Sharron Angle .

The television ad 's narrator begins , `` For a victim of rape or incest , Sharron Angle would force her to have the baby . ''

The ad then plays audio of Angle . `` Two wrongs do n't make a right . ''

Craig Varoga , a longtime Democratic strategist who runs Patriot Majority , told CNN his group will significantly step up spending in the final three weeks before the election . Varoga expects to raise and spend as much as $ 10 million on the Reid race and other key Democratic races around the country .

Varoga says his group is funded mostly by labor unions , in-state individual supporters and nonunion progressive groups , but he did not provide the names of these groups . Watchdog organizations say transparency is still a problem with these groups .

`` They do n't have to do it -LSB- reveal donors -RSB- in real time , '' said Levinthal of OpenSecrets.org . `` If they put a television ad up , there 's no disclaimer at the end of the advertisement saying that this ad was paid for by these different corporations or these different unions .

`` In fact , since Patriot Majority raised most of its money in the past few months , recent Federal Election Commission filings do n't reveal the majority of its donors . Patriot Majority 's third quarter FEC filing is due this week -- three weeks before the election -- and will list the more recent donors . ''

Varoga laments that Democrats are lagging behind Republican efforts to use these new political identities to raise large sums of money .

`` They are Goliath , and we are David , '' he said . `` We are fighting back , and we 're going to use the slingshot that we have in order to fight this fight . ''

Another super PAC is American Families First Action Fund . It 's an outside group organized primarily by a Democratic insider , who once headed up Democratic Party efforts to elect members to Congress . He helped start the group five weeks ago to compete with Republicans .

And although American Families First Action Fund is required to disclose who funds it , CNN is told that the group itself was one of the secret donors to the Defenders of Wildlife Action Fund in its ad against Pearce . It is a hard trail to follow , which underscores the point that Democrats , too , are trying to play carefully in what the president calls a shadowy world .

In fact , while American Families First Action Fund may be a super PAC that must disclose its donors , it has a sister organization , Americans Families Fund Inc. , which does not .

Multiple Democratic sources tell CNN there is great frustration in some Democratic circles with the president 's attacks on Republican groups .

These sources say the president has made it harder to persuade Democratic donors to contribute to their outside groups , which for better or worse , are emerging as significant players in this year 's election .

@highlight

Political groups operate outside parties and do not have to reveal members or donors

@highlight

It 's difficult for voters to figure out who is behind messaging , watchdog group says

@highlight

President Obama has attacked groups for spending millions without disclosing donors

@highlight

Democratic-leaning groups are also cloaking their funding sources , however